Reverse Engineering the Oculus Rift DK2's Positional Tracking Tech

← Back to Stories (view on slashdot.org)

Reverse Engineering the Oculus Rift DK2's Positional Tracking Tech

Posted by timothy on Thursday October 9, 2014 @04:57AM from the blink-and-you-won't-miss-it dept.

An anonymous reader writes The Oculus Rift DK2 VR headset hides under its IR-transparent shell an array of IR LEDs which are picked up by the positional tracker. The data is used to understand where the user's head is in 3D space so that the game engine can update the view accordingly, a critical function for reducing sim sickness and increasing immersion. Unsurprisingly, some endeavoring folks wanted to uncover the magic behind Oculus' tech and began reverse engineering the system. Along the way, they discovered some curious info including a firmware bug which, when fixed, revealed the true view of the positional tracker.

8 of 26 comments (clear)

Min score:

Reason:

Sort:

40 years later, Twinkle Box makes a comeback. by Animats · 2014-10-09 05:13 · Score: 5, Informative

The Oculus Rift tracking method, with various lights blinking at different rates, was first used in Twinkle Box, in 1974. It was really clunky then. They had to use rotating-disk cameras because vidicons had too much lag, and the wearer had to wear a big electronics box. Same idea, though.
Article barely mentions me... by Jherico · 2014-10-09 05:21 · Score: 4, Interesting

I think that the article kind of unfairly glosses over my contribution. I posted the original reddit thread, and I'm the one who discovered the codes required to actually enable the LEDs on the device. I appreciate that Oliver is an actual VR researcher, but I did this in part to get some visibility for the book I'm writing on Oculus Rift development.

--
Jherico
What can the average user can do to ensure his security? "Nothing, you're screwed"
1. Re:Article barely mentions me... by blueshift_1 · 2014-10-09 05:42 · Score: 3, Insightful
  
  Welcome to the internet where the facts are made up and citations don't matter...
2. Re:Article barely mentions me... by Jherico · 2014-10-09 05:50 · Score: 4, Interesting
  
  Anyone with the SDK can get these codes. Oh, and you made a thread on Reddit.
  Really? Oliver explicitly said he'd had no luck in getting the codes. The SDK doesn't contain them, btw. Only the Oculus runtime, which is closed source, now communicates with the hardware. So, anyone who had the SDK and could also figure out how to write a DLL to intercept the HID calls made by the runtime (not the SDK, which doesn't contain the codes anywhere) could get the codes.
  
  --
  Jherico
  What can the average user can do to ensure his security? "Nothing, you're screwed"
3. Re:Article barely mentions me... by ArcadeMan · 2014-10-09 05:53 · Score: 4, Funny
  
  Welcome to the internet where the facts are made up and citations don't matter. - ArcadeMan
  
  --
  Get free satoshi (Bitcoin) and Dogecoins
4. Re:Article barely mentions me... by Jherico · 2014-10-09 07:00 · Score: 2, Insightful
  
  It's not hard to monitor HID, lol. None of this is hidden, buried, or secret. It's just not published. Anyone who has the SDK can easily do what you did.
  Thank Captain Hindsight. Sure, technically anybody could have done it. But no one else actually did it, despite the numerous Linux developers complaining about the total lack of positional support for them. It's pretty easy to look at someone else's work and say "Oh, yeah, that's obvious" once they've actually done it. I don't really see why you've bothered commenting since you seem to be of the opinion that the entire exercise was pointless. If you don't buy into the entire premise of the article how can you be bothered to have an opinion of whether one of the participants in the work received proper credit?
  
  --
  Jherico
  What can the average user can do to ensure his security? "Nothing, you're screwed"
Article mentions me! by Jherico · 2014-10-09 06:20 · Score: 4, Informative

Never mind. They've corrected the article.

--
Jherico
What can the average user can do to ensure his security? "Nothing, you're screwed"
Re:Linux by Jherico · 2014-10-09 10:20 · Score: 3, Interesting

I understand this point of view, but on the other hand, I think that the VR killer app hasn't been found yet. The 'mainstream' equation works both ways. Sure there's a bigger potential customer base for VR apps running on Windows and OSX, but I think there's a bigger 'idea base' for new VR apps with hackers running Linux.

--
Jherico
What can the average user can do to ensure his security? "Nothing, you're screwed"